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Deer Tick (Ixodes dammini) Larvae

Throughout the woods of North America, the tiny deer tick (Ixodes dammini) is rapidly replacing the mythical "Boogeyman" and the fabled big, bad wolf as a means of imparting caution and obedience to children, in the face of fear. Since the 1980s, nymphal and adult deer ticks have acted as the vector for Lyme disease in North America.

The adult deer tick is described as the size of a sesame seed (2.5-millimeter diameter), oval, and with a flattened body before enjoying a blood meal. When engorged, the eight-legged arthropod is about the size of a small pea and blue-black in color.

The etiological agent of Lyme disease, named for Lyme, Connecticut, the type locality for the zoonosis, is the spirochete Borrelia burgdorferi. This member of the hard tick family of arachnids spreads the pathological bacteria from infected host to other hosts with the larval or nymphal host, a rodent, acting as a reservoir, and an infected tick carrying the spirochetes its entire life. Some deer ticks can also cause tick paralysis and the protozoan infection caused by Babesia microti. Lyme disease is characterized by arthritis, cardiac, and skin symptoms and is also reported in dogs. Migrating birds bitten by an infected tick are believed to help spread deer ticks and their zoonoses.

In its three-step process of parasitism, larval deer ticks feed on the ears of white-footed mice while nymphs attach to humans, dogs, horses, rodents, and cattle. Adults, as the name implies, feed on the preferred white-tailed deer, as well as humans and other mammals. Blood-engorged females lay approximately 3,000 eggs and the larvae, nymphs, and adults feed on separate hosts. The entire life cycle takes about two years to complete.